Gear hobbing machine



Sept., 10, 1940.

F. LUX

GEAR HOBBING MACHINE Filed June 27, 193s s sheets-sheep 1 IJYVENTOR Frederick Lux.

ATTO

Septu 10, 1940. i F, LUX 2,234,504

GEAR HOBBING MACHINE Filed June 27 1955 3 Sheets-Sheet 2 ,INVENToR Frederick Lux ATTORN septo O, 1940@ F, LUX 2,24504 GEAR HOBBING. MACHINE Filed June 27, 1936 3 Sheets-Sheet 3 Fredemch Lux j* ATTORNEY Patented Sept. 10, 1940 GEAR HOBBING, g Frederick Lux,wa.terby,on, Application June 27, 1936, Serial No. f8!7, "04` y 12 Claims. This invention relates togear cutting machin'es,l and more `particularly-to an automatic` First, it has been dicultto design a hob v spindle mounting and drive sufficiently small to and at the 'same time, strong enough to 'be satis'factory in service; f

Second., in view of the fact-that ra pinion blank is relatively short, much 'time is lost while 20 the hob is approaching the pinion and in the initial cutting th'ereofuntil the Vfull depth of the tooth cut is reached; and

Third, the mechanism 'for automatically feeding pinion blanks int'o hobbing position was quite complicated.

By means 'of the present invention, the above and yother disadvantages have been overcome.

One object of this invention .is to produce a hobbing machinewhich will automatically feed the pinion blanks into cutting position, and automatically eject them from the machine after said blanks have been properly cut.`

A further object is to provide a machine of the above nature having means for moving the Il?) pinion blank up to the cutting periphery of the hob at a rapid rate of speed, and in which the initial cutting of the blank will be performed at a relatively high rate of speed until the full depth of cuthas been reached, and in which the movement ofthe blank is then slowed down to a uniform speed for'cuttingthe main portionk of said blank.

A further object of the invention is to provide a machine of the above nature in which it is 41' unnecessary to alter the cutting feed of the mafohine when cutting pinions of the-same length, but of varying number o f teeth. l

A further Objectis to provide a machine of the above nature having improved means for accurately and minut-,ely adjusting the angular and vertical positions of the cutting hob in accordance with various types of gears and pinions that may be out upon the machine.

A further object of this invention is to proa, videan automatic hobbing machine which will be applicable to the hobbing of small pinions,

(creo-g3), Y

berelatively simple-"and `inexpensive to manu'- fatu'rei easyftooperate, Awhich will incorporatek allthe advantages ofthe hobbingp'r'ocess and n'iake thein'- applicable-to the manufacture of smallpinions, 'such as are used. in small clocks 5 and v"wditches,"'and which will bever-y eifcie'n't and durable in use.

`With fthe'seand other 'objectsin view there" has been 'illustrated on the "accompanying"'draw-r ings one `'for'min which the invention may be conveniently embodied in practice. f 1

In 'the drawings: r' f 1 represents a front elevation'of the alitomatic )hobbing machine with the yblankie'edi'ifi'g magaZ'ineo'-litte. 'v 1 f" Fig. 2 s fa plan view of the same. f

f `g. 3 i'saright-hand end elevational 'View ci' the machirle,` showing themagazine attached thereta Fig. 4 is la longitudinal vsectional viewthro'u'gh the hobbing 'cutter mechanism, 'the view being taken substantiallyalong the line j Q4 of Fig. '2, looking intheA direction of the. arrows.

"5 is a longitudinal sectional ,view of the machine taken'sbstantially along vthe lineS-S of Fig. -2 an, cl on the line 5-.'5 of Fig. 3, lookingk in the direction ofthe arrows. 1 f

Fi-g. 6 fis a diagrammatic perspective viewshowing the arrangement o'f thevario'us gears, cams, shafts, and other interior'mechanism.

Fig. 1 "is `afperspective view,` on a 'greatly enlarged-scale, ofa typical blank fed by the magchine, which includesva dish-like bottomfcatch pan or. basin I I, havinganintegral, upstanding rectangular lubricant containingfhousing' I2 for encas'ing the principal.V gear. mechanismy of y the machine.- Thehousing I2 is open at the top and is adapted to be closed by a relatively heavy cover plate I3 attached thereto as .by cap-screws I4. The cover plate I3 is yprovided with a dovetailed slot I 1 (seewliig. 3) for supe,y

porting areciprocating'work-carrying slide yI5 and also aneadjustably mounted cutterhead casing I6,v which .parts will be hereinafter more fully described. .The slot II is adapted toslid-` ably receive a corresponding dovetailed section` Iformed integral with and depending from the under side of said slide I5.

M ain drive mechanism The main drive mechanism, which is best shown in Figs. 5 and 6, comprises a main shaft 2|] supported at one end by an upright standard 2| formed integral with the left end of the basin |I, and suitably journaled therein by means of a bushing 2|a. The shaft 20 is also suitably journaled in the housing I2 by means of an intermediate bushing 22 and a bushing 23 located in the opposite wall of the housing I2. Another intermediate support for the shaft 20 comprises an upstanding bearing member 24 formed integral with the bottom wall of said housing I2.

A grooved driving pulley or sheave 25 is attached to the left end of the main drive shaft 20, as viewed in Figs. 5 and 6, and may be connected by a belt, not shown, to a suitable source of energy such as an electric motor, not shown. The extreme right end of the main drive shaft 20 is provided with a reduced section'2lla. having a spur gear 26 whichis clamped thereon by a clamping nut- 211. The spur gear 26 `is adapted to drive an index'gear 29 keyed on the right end of a back shaft 30 which `also passes entirely through the machine parallel to the main drive shaft 20.

An idler gear 28 is rotatably supported at the free "end of a swingable bracket 3| by means of a-journal stud 32. the bracket'l vis formed with a reltaively large gearing hole 33 which is adapted to engage about a cylindrical bearing head 34 herein shown as an integral part of the main shaft bearing bushing23(see Fig. 5).'

The upper end of the idler gear bracket 3| is split at 35, and the side sections thereof are clamped tightly aboutthe head 34 by a binding screw y36. By means of this construction, the bracket 3| may be swung to one side whenever 1 desiredvto permit changing of the gear 29 on the shaft 30v according to the number of teeth on the pinion being cut.

The back shaft 3|).is suitably journaled in the right-land left walls of the housing I2 respectively by means of bushings 31 and` 38 carried Reciprocating 4worlc-carrying slide 'Asbest show n in Figs. 1, 2 and 5, the workcarrying slide I5 has an integral enlarged hollow fhead 39 at its left Vend from which extends a rearwardly offset upper gear housing 40 located on avertical axis. Depending from the housing 40 there is providedla tubular casing 4I terminating at its lower end in an 4enlarged lower gear housingY 42. Thelower gear housing 42 has a laterally offsetrcup-shaped gear casing 43, positionedA to the rear thereof (see Fig. 2). .All of the above parts designated by the numerals 39, 4 0, 4|, 42 and 43 form component parts of the work slide I5, and consequently reciprocate with it as a unit.A j

`The cupped casing 43 is positioned vwith its axis coinciding with the axis of the back shaft 30 which extends through said cup 43, as best '-shown in Fig. 2. Ay spiral gear 44 is rotatably coniined within the cupped housing 43 by means of an end thrust cover member or cap 45 suitably attached to'the open end of said housing 43. The spiral gear 44 is provided with a suitf able key which is adapted to slidably engage in The upper' opposite end of a longitudinal grooved key-way 46 cut into the peripheral surface of the back shaft 30.

The slidable spiral gear 44 intermeshes with a spiral gear 41 located in the lower gear housing 42 and keyed to the lower end of a vertical index shaft 48, which extends upwardly through the tubular casing 4| and is suitably journaled therein.

A worm 49 is carried by the upper end of the shaft 48 and intermeshes with a worm wheel 50 keyed to the left end of a rotatinghead stock shaft 5I, being held in place by a locking nut 52. One end of the headstock 5I is journaled in a bushed bearing 53 forming a part of the housing 39, while the opposite inner reduced portion of the headstock shaft 5I, as shown in Fig. 5, is journaled in another bushed bearing 54 forming an upstanding integral part of the work slide I5.

The inner end of the headstock shaft 5| is provided with a tapered socket for receiving a workdriving spindle 55 tapered at both ends, the inner end of said spindle 55 being adapted to receive one end of a journal shaft 56 of a pinion blank 51, as shown in Fig. 7. The intermediate part of the blank 51 is formed with an enlarged cylindrical shaped section 58 adapted to have gear teeth cut thereon, and said blank terminates in reduced trunnions 56a adapted to tightly fit into the socket of said spindle 55, whereby the blank 51 will be rotated by said driving spindle by the action of friction.

The right-hand end of the gear blank shaft 56, as viewed in Fig. 7, is looselymounted to rotate freely in the tapered exposed end of a work support tapered spindle 59 which engages in a tapered socket provided in a tailstock shaft 60. The shaft 60 is suitably supported at its inner end by meansof a bushed bearing 6|, and at its outer end in another bushed bearing 62, both of which bearings forming upstanding intgeral parts ofthe work slide I5. It will be understood that the tailstock shaft 6l) and attached tapered spindle 59 do not rotate in the bearings 6| and 62, but merely slide coaxially therein.

Work slide actuating'v mechanism In order to move the revolving pinion blank 51Minto the path of a rotating gear-cutting hob 63 carried at the forwardvend of a horizontal rotating hob spindle 64, at a greater speed than the normal cutting speed, provision ismade of a cam controlling mechanism for operating the work slide now to be described. As best shown in Figs. 4 and 6, thevshaft 30 carries a rigidly keyed horizontal worm '66 which is adapted to intermesh withv a worm wheel 61 carriedby a vertical relatively short shaft 68. As shown'in Fig. 4,' the lower end of the shaft 68 is suitably journaled in a hushed bearing boss 69 forming an upstanding integral part of the -housing base, while the upper end of said shaft 68 in turn is journaled in a bushed bearing 10 provided in the cover plate I3 of the housing I2.

Above the worm wheel 61 and rigidly carried by the shaft 68 is a worm 1I, which intermeshes with a' worm wheel 12 keyed to the inner end of a horizontal cam shaft 13. The forward end of the cam shaft 13 is journaled in a suitable bearing support 14 forming an integral part of the upstanding support 24 previously mentioned (see Fig. 5). The rear end of the cam shaft 13 in turn is journaled in a bushed bearing boss 15 which, as shown in Fig. 2, forms an integral part of the rear wall of the housing I2. The shaft 13 extends through the rear of the housing I2 and has a slide operating cam 16 removably secured thereto by means of a nut 13a..

The peripheral working surface 16a, of the cam 16 (Fig. 6) is adapted to be engaged by a lfollower roll 11 pivoted to the outer 'bifurcated end 18 vof an upwardly inclined swinging arm 19. The lower end of the arm 19 is formed withan integral hub 12a which is preferably integral with the outer end of a rocker shaft which extends into the interior ofthe housing `I2 and s journaled in a bearing boss 8| in the rear wall of said housing (see Figs. 3 and 5) The front end 82 of the rocker shaft 80 is reduced and journaled in a suitable bearing boss 83 in the front wallof the housing I2. The intermediate portion of the rocker shaft 80 adjacent the front bearing is provided with a tapered section 8d for receiving a hollow hub 85 forming the integral lower connecting part of an upwardly projecting workslide-operating lever |56.l As clearly shown in Fig. 5, the upper end of the lever 86 is provided with a flat faced head 01 which Vis adapted to engage against ythe inner end of an adjustable horizontal setscrew 88 threadedly engaged in a tapped hole provided in a depending portion 89 forming an integral part of the left end of the Work-slide .|5. The set screw 33 is adapted to be retained in any desired adjusted position by means of a lock nut 90.

The work slide i5 is adapted to be moved lby the action of the cam 16 to the right for' feeding the pinion blank 51 against the cuttinghob 63 against the influence of a relatively strong helical spring '8| which is located in an elongated groove 92 formed in the under surface of the work slide l5, as best shown in Fig. 5. The left endcf the spring-9| (see Fig. 5) is attached to a suitable anchor bolt 93 connected to a stationary lug plate S4 secured to the left end of the housing` cover plate I3. The right end of the spring in turn is connected to a depending anchor pin 95 depending from the work slide I5, and the tension of the spring `tends to return the slide to its normal left end position. When the Work slide has been moved as far as it will go in the lefthand direction by the spring 9| and under the control of the cam 16, the work spindles 55 and 59 will then be in properposition to discharge a cut pinion and receive a new pinion blank as will be later described.

Pinion blank magazine The magazine for feeding the pinion blanks 51 is clearly shown in Fig. 3, and comprises a supporting bracket @ti attached to theforward end of a pair of supporting arms 9 1 and 98,'projecting forwardly and formed integral with the spindle bearings 54 and 6|, respectively. The supporting bracket S6 includes an upwardly rearwardly inclined longitudinal arm 96a adjustably carrying a fulcrum stud 99a at its upper end. A depending cam-operated inclined lever Q9 is swingably supported upon the stud 99a and carries with it a magazine guide |00 attached to the forward face thereof. The lower extremity of the guide |00 isl curved forwardly, so that its discharge end will be positioned in relatively close proximity to the feeding station of the machine.

In order to impart swinging motion to the lever S9, a forwardly extending angular arm IUI is car-l ried by the lower end of the said lever, and has an adjustable lever |02 pivotedthereon by means of a pivot pin IZa. The outer end of the lever surface of a .sector cam IMmade secure to a cam shaft |05.. The upper end of the lever |02 is lprovided with an adjusting screw 106 threadedly engaged therein, and adapted to have its .inner end abutting against the adjacent surface of the angular 'arm .|0I. By adjusting the set screw |06, it will be readily understood that the feeding end of the magazine |00 can be vbrought into proper alinement with 'the working center line of the machine.

To hold the roller |03 in constant peripheral engagement 'with the cam |04, it being understood that the face of the cam |04 is of sufficient widthv to permit maximum movement of the slide I5 without the roller |03 becoming disengaged therefrom, provision is made of a vertical helical tension spring |01 'having its upper end secured toan anchor pin `MHVattachedto the upper hub part of the magazinecam lever 99 and projecting forwardly therefrom. The lower end of the spring |01 is made secure to a stationary pin |09 projecting forwardly `from the rcross-member of the bracket 95.

Magazine kfeeding mechanism In order to operate the magazine |00 so that the blanks willbe fed automatically'into the working center of the `machine in proper synchronismv with the other mechanical operations of .the machine, the slide-operating cam 16 oarries a forwardly-.projecting trip pin |I0, which is adapted'to engage withI a wedge-shaped nose I I on the end of a trip arml IZatt'ached to the outer rear endof a longitudinal horizontal rocker shaft I I3. The rocker shaft ||3 extends transversely through the housing vI2 and is journaled in the front andrear vwalls thereof. Attached to the forward end of 4this shaft II3, provisionis made of a clutch engaging arm ||4 carrying a depending clutch pin |I5 at its outer free yend, which is adapted to operate a clutch member IIB.

The clutch member I-II is supported on a relatively .short horizontal clutch shaft II 1, having its .rear end journaled in an opstanding support II 1a forming an integral part of the vhousing base. The forward end of the clutch .shaft I I 1 in turn is journal'ed in a bushed bearing ||8 (see Fig. l) forming an integral part 4of the front wall of the housing I2.

The clutch IIB is adapted tobe actuated from the main drive vshaft '20 through the medium of a worm pinion I I9 keyed to an intermediate part of said shaft andl intermeshing with la worm wheel |20 mounted to freely rotate on the clutch shaft II'I. The clutchcomprises two interlockable cooperating parts, which for convenience will be called theV toothed rotating clutch section |2 and the axially slidable detent member |22. The toothed member|2| `is constantly rotating by reason of the fact that it forms an integral part of the worm wheel |20. Whereas, the detent member |22, on the other hand, is slidably keyed to the shaft H1 for permitting said member I 22 to slide upon said shaft IIl'into andout of engagement with the constantly rotating detentv provided with a peripheral cam groove |23 which extends substantiallyv about the entire circumference of said clutch member |22 with the exception of al detent bridge member |22, which interrupts the groove.V The clutch pin I I5, previ'- ously mentioned, projects into this groove and 75 ifi normally engages against one side of the bridge member |24. The diameter of the pin 5 is made substantially less than the Width of the groove |23, andthe end of the groove 23 in which the clutch pin I|5 travels has the outer left-hand face thereof, as viewed in Fig. 6, provided with an inclined surface for exerting a camming action on the pin ||5. The sliding clutch member |22 is pressed rearwardly at all times by a light compression spring |21 surrounding the clutch shaft ||1, and having one end thereof engaging against the adjacent face of said member |22 while the opposite end engages the inner surface of the front wall of the housing |2. l

When the trip pin |0 carried by the slide operating cam 16 engages the nose it will be apparent that the lever ||4 will be raised lifting the clutch pin |55 out of its normal position in the end of the groove |23 clear of said groove and the intersecting bridge |24. This will permit the spring |21 to slide the clutch member |22 rearwardly so that its innermost toothed edge will interlock with the constantly rotating `toothed clutch member |2|, and thus set the clutch shaft H1 in rotation. The clutchpin ||5 carried on the end of the arm ||4 will drop back into the groove |23 as soon as the detent |28 formed in the under edgel of thev trip lever ||2 rides over the trip pin ||0. The positive rocking of the shaft ||3 and the trip lever ||2 downwardly is insured by a spring |29 having its upper end connected to a pin |30 projecting laterallyfrom the arm .||2, while the opposite end of the spring is secured to the rear wall of the housing |2.

When the clutch member |22 is nearing the end of its rotation, the clutch pin i l5 will engage the inclined cam surface |25, and will cause said member |22 to slide forwardly, disengaging the clutch teeth from each other and stopping the rotation of the shaft i1.

The intermittent rotation of the shaft I1 is transmitted to the magazine feed shaft |05 through a pair of spiral gears |3| and |32 keyed respectively to said shafts I l1 and |05, and preferably having a one-to-one tooth ratio. The magazine feed shaft |05 (as best shown in Figs. 1 and 2) is journally supported in the front of the machine, outside ofthe housing l2, by a pair of spaced upright standards |33 and |34 formed integrally with the front edge of the tray When the feed shaft |05 is making one rotation, the roller |03 carried on the end of the lever. |02 carried by the swinging lever 99 will engage the high surface of the sector cam |04 and hold the magazine |00 in normal inactive position. As the cam |04 rotates, the roller |03 will be caused to drop to the lower surface of the cam |04, causing the feeding end of the magazine |00 to be moved into coaxial alinernent with the spindles 55 and 59, positioning a pinion blank between said spindles. The blank will then be picked up by said spindles, after which the magazine |00 will swing back to its normal inactive position. The shaft |05 will always come to rest with the roller |03 resting upon the high surface of the sector cam |04.

Pinion knockout mechanism Before the feeding operation of the magazine |00, it is first necessary to remove the previously cut pinion gear 51 from the work spindles 55 and 59. This is accomplished by a knockout mechanism operated from the feed shaft |05, f which first disengages the slidable spindle 59 from the adjacent end of the pinion blank shaft 56 and then forces the opposite end of said blank shaft 56 out of the end of the rotating spindle 55. The mechanism for accomplishing this result, and which is best shown in Figs. 2, 3, 5 and 6, includes a rockable knockout lever |35, positioned to the right of the Work slide |5, and pivotally supported in the outer end of a bifurcated bracket |36 projecting from the right of the feed slide 5. The knockout arm |35 is fulcrumed in the bracket |36 by means of a pivot stud |31. In order to operate the knockout lever |35, the outer lower end of said lever |35 carries a cam-engaging roller |38, which is adapted to be engaged by The ejector cam normally comes to rest at 'L its lowermost position, as best shown in Figs. 1', 3 and 6, when the feed shaft |05 ceases to rotate, and the particular construction of this crescent shaped cam |40 is such that when the work-- carrying slide is moved to the right during the gear cutting operation,l the roller |38 on the end of the knockout lever |35 will clear the top edges of said crescent-shaped member |39 without interference.

The upper end of the knockout lever |35 has an integral cylindrical head |35a, which is adapted to engage within a transverse slot |42 provided in the adjacent rounded edge of a yoke member |43. The yoke member |43 is adjustably secured to the outer threaded end of the tailstock spindle 60 by means of a pair of opposed nuts |44, which also serve to confine the cylindrical head |35a within the transverse slot |42 of said yoke |43. Movement of the tailstock 60 to the right by the knockout lever arm |35 is effected against the influence of a compression spring 60a surrounding said tailstock and abutted against the adjacent face of the bushed bearing 62 and an adjustable collar 60h secured to said tailstock. It will be evident from this construction that as the knockout lever |35 is operated by the crescent-shaped cam |40, the tailstock 60 will be slid to the right within its respective bearings 6| and 62 a sufficient distance to permit the right-hand work support spindle 59 to clear the trunnioned end of the gear blank shaft 56.

In order to eject the finished hobbed pinion 56 from the left-hand rotating work spindle 55, provision is made of a relatively small slidable knockout rod |45 connected to the yoke |43. As best noted in Fig. 2, the right end of this knockout rod 45 carries a pair of locking nuts |46 and a collar member |41, which is abutted against the adjacent face of the innermost nut. A slight space is preferably left between the adjacent faces of the collar member |41 and the yoke member |43 for the purpose of permitting the tailstock 60 to move a distance sufficient to cause the end of the spindle 59 to clear the end of the blank 56 before any motion is imparted to the slidable knockout rod |45. Movement of the knockout rod |45 to the right is effected against the influence of a coiled compression spring |48 abutted between a collar |49 secured to said rod |45 and the adjacent face of the tail stock bearing 62.

The knockout rod |45 is slidably supported in the three bearings 54, 6| and 62, and has attached to its extreme left end an ejector block |50 which is adapted to slidably embrace the rotating headwhich is fitted into the hollow socket of.- the head Astock as previousiy explained, hasv a. longitudinal smaii ejector pin |54 located lconcentrically therein,V and passing through substantially the entire length of said spindle with its outer end positioned adjacent the end of the pinion blank spindle 56. The opposite end of the knockout punch |54 is provided with any enlarged head |55 which telescopically engages within one end of a cylindrical chamber |56 provided Within the spindle 55, and which is adapted to abut against the transverse pin |52' being held thereagainst by a small helical spring |51 housed within the chamber |56 and surrounding the ejector pin |54, Obviously, when the ejector block |50: is moved to the right, the ejector pin |54 will force the completed hobbed pinion 51 out from the end of the Work spindle 55.

Adjustable hob-cutter head The cutting of the teeth of the pinion 58 is laccomplished by means of an angularly adjustable hobbing unit |58 superimposed upon the cover plate |3, and carrying the cutter hob 63 previously mentioned.. The unit comprises a cast metal housing |59, including a hollow vertical cylindrical portion |60 and a laterally offsetv integral gear housing |6|, both parts' of which are open at the top and adapted to be closed by a unitary detachable cover |62. l

The cylindrical portion |60 of the hobbing unit, as best shown in Fig. 4, is designed to adjustably fit about a vertical tubular supporting post |63, the lower end of which is slightly reduced in .diameter and. adapted to havefa tight t in a cylindrical opening |64 provided in the housing coverplate I3. The post |60 fits against theI top surface of an annular pad |65 provided onrthe top of the cover plate I3, and said post is tightly secured to said plate by a large nut |66 having screw threaded engagement with the lower threaded end of the post and binding against the under surface of said cover plate |3.

Poweris transmitted to the rotating cutter hob 63 through a vertical hob-driving 'shaft |61 (Fig. 6) suitably journaled in a pair of spaced flanged bearing bushings |68A and |69., secured within the fixed tubular post |63 (see Fig.. 4). A large spiral gear |10 isr suitably keyed to the lower end of the vertical shaft |61 and is held in place by a. clamping nut |1|'. The spiral gear |.1:0 is adapted to intermesh with a similar spiral gear |12 positionedat right-angles thereto. on a. horizontalaxis, and keyed to an `intermediate `part. of the main drive shaft within the housing |2. The upper end of the vertical. shaft |61 carries a. small spiral gear |13 which. is adapted to intermesh with a relativelylarge spiral gear |14 conned within the gear housing |6| and suitably keyed to the horizontal hob carrying spindle 64. .The gear |13 engages the spiral gear |14 through a suitable opening |15 provided Within the side wall of the tubular post |63, as shown in Fig. 4.

The hob carrying spindle 64 is journaled within the'gear housing |6| by means` of a spindlebearing hub |16 projecting from the forward Vface of the oiset housing 6|I and another bushed vbearing |16a projectingY from the rear-.face of said housing |6| (seeFig. 2)'. Vertical. and angular adjustment ofhobbing um't yThe width of the faceof the spiral gear |13 on the Vertical shaft |61 is made wide enough to permit the gear |14' to be raised and lowered with respect thereto without .becoming operably disengaged. The adjustment ofthe gears |13 and |14 relativeto each other is accomplished' by raising and lowering the housing |59 with respect tothe ,supporting post |63. The vertical adjustment of the housing |59 is effected by the employment of two relatively large opposed upper and lower iEffi knurled nuts, |'11 and |18. The nuts |11 and |18, '1"5 as best shown in Fig. 4,v are located at opposite ends of the cylindrical portion |60 of the housing |59 and havel screw threaded engagement with spaced threaded endr sectionsy |19 and |80v of the tubular post |63., The lower nut |18 is adapted to beinterposed between the pad |'and the cylindrical portion |60 of the housing for supporting! the entire weight ofv the` adjustable unit thereabove. kThe. top open end of the'tubular post |63 projects above the cover .member |62 and is adapted to be closed by a angedycap |8| to permit theintroduction of' lubricant yand prevent the entrance of foreign matter, and said cap may be readily removed to permit access to the interior mechanism. f

InA order to obtain the desired angular adjustment of the `hobbing unit |58 about the vertical axis of the post. |63, and thereafter lo-ck said unit inadjusted position, provision is made of an outboard support. |82 having an arcuate base |83 and anv upstanding arm |84. The arcuate base |83 isadjustably supported on a pad |85 formed integral. with the tcp surface of the cover plate i3, and said basel |813. is provided with a pair of opposite elongatedl end slots |96, |86 for receiving bolts |81, |81 to connect itwith said pad |85. (see` Fig. 4).

The upperend ofthe upstanding arm |84 isprovided with van integral vertical elongated slottedhead SSwhich. is adapted tobe positioned in side-by-side relationship with a lateral` lug or vear |89 integral with the gear housing |6|, as. best shown'in Fig.. 4. Provision is also made of a locking screw |90 having. threaded engagement .in the v lug |83 vand slidable in the elongated slotted head |88.4 l

order tov permit accurate adjustment. of .the

ygear hobbing unit.,I a graduated scale lillis provided in the top surface of the pad |85, as shown in Fig. 2. Moreover, if desired, the adjacent surface ofthe arcuate base |82 may also be graduatedA With a. verni-er scale (not shown) to increase the accuracy of thesetting. Another scale |592, asshown'under' .the cut-away section. of the casing i6 in Fig. 2, is provided on the top surface of the bottom nut` |18 for indicating the heightA of thecutter` by reference to a setting mark |93' (see Fig. 3) on a flattened iinished pad |94 formed at the lower end of the cylindrical `section |60.

To set the hobbing unit |58. into cutting position for a specific pinion, the upper nut |11 will .first be loosened, after which the bolts |81, 1281 will also 'be loosened.4 The unit |58 will then be moved around the post |63. as far as required for the dimensions and type of. gear to be nabbed,- the exact setting being shown by the graduated scale- |9| The bolts 1|81 will vbe tightened, thus completing the angulargadjustment. Inl orderto make 'the necessary vertical Aad- Vthe end of the driving spindle 55.

justment of `the hobbing' unit.4 |58',` theI locking screw |90 at the left of the housing |6| (Fig. 4) will be loosened slightly. e The housing |59 will then be moved upward 'lor downward to the desired vertical position by manipulating the top knurled nut |11 and thelower knurled nut |18.

"The unit will then be locked securely in vertical adjusted position by Htightening `the upper nut |11 andthe screw |99.

Hob cooling and lubricating system To provide for the necessary cooling and lubrication of the hob 53 in cutting the teeth of the pinion blank 51', provision is made of an angular lubricant supply tube |95 pivotally mounted in the front end of a raised hollow boss |96 formed integrally with thetop of the cover plate |62. The lower end ofthe tu'be |95 is formed with a flattened restricted nozzle |91 for the purpose of distributing lubricant over the entire surface of the cutting hob 63. The nozzle Vend |91 of the tube |95 is adapted to be located adjacent the cutting surface of the hob '63, but may be swung out of the way when desired'. A fluid conductor |98 is suitably connected to the rear enlarged end |99 ,of the boss |91 and` may be controlled by` a 'suitablepetcock (not shown) located anywhere in the Vline of the luid conduit.

Operation In the operation of the machine, when the power is turned on, the hoby spindle 64 and the cam 16 at the rear of the machine Will start to rotate. This will cause the pin ||0 carried by said cam to come into contact with the wedge nose of the trip lever l2, liftingv the arm` ||4 and allowing the springV |21 to throw the clutch mechanism ||6 into operation, thus causing the magazine-operating shaft |05 to rotate. The rotation of the shaft |95 and the sector cam |04 carried thereby permits the roller |03 to drop from the high section of said cam to the lower section thereof, causing the magazine |99 to deliver a pinion blank 51 into coaxial alinement with the spindles 55 and59.

Previous to the feeding operation of the magazine, the crescent cam |40 at the right-hand end of the shaft |95 will have swung the knockout lever |35 about its pivot |31`and moved the tailstock 69 carrying the spindle 59 a short distance to the right for the purpose'of vpermitting the initial gear blank 51 to be fed into the working center of the machine without interference. When the gear blank 51 is properly arranged between the spindles 55 and 59, the tail stock 69 will be permitted to moveto the left under the expansion of the spring 69a so that the socket of the work spindle 59 will slip over the trunnion 56a at the right-hand of the spindle 56. Further movement of the tailstock 69 to the left will cause th-e trunnion 56a at the left end of the spindle 56 to be inserted into the socket at rIfhe friction between the blank 51 and the socket of the spindle 56 causes said blank to rotate With the head stock shaft 5|.

When the blank 51 is thus held in hobbing position, the delivery 'end of the magazine |90 will swing out of the way under the control of the sector cam |94 and the roller |93.

The pinion blank 51 having thus been properly located and "set into rotation, the workcarrying slide I5 will immediately start to travel to the right, as viewed in the several figures, at a rapid speed determined bythe shape of the cam '16."vTh'e enlargedy cylindrical section 58 of the pinion blank 51 will then engage the hob 63, and the initial cutting operation by the hob 63 will be effected at a diminishing rate of speed until the fulljdepth of the gear tooth is reached. The slide l5 Will then be advanced by the cam 16 at a uniform slower rate of speed for the remainder of the hobbing cut, said speed being in accordance with standard gear cutting practice. By the use of properly proportioned gears, interconnected as shown, and all of which are driven from a common drive shaft, a predetermined relation is obtained between the speed of the hobbing cutter 63 and the speed of the pinion blank 51 whereby axially directed pinion teeth will be cut in the blank as it is fed in the direction of its aXis beneath the hob 63. This arrangement of interconnected gears, of the form shown, permits the cutting of teeth on blanks of diierent sizes by the simple expedient of substituting different idler gears 28 to ob tain the proper relation between the speeds of the size of blank 51 to be cut, and the hobbing cutter 63 required for cutting such teeth. The

work slide l5 will then be retracted to its normal left-hand position (as best shown in Figs. 1 and 5) by the action of the strong spring 9| located .underneath said slide. It is to be noted at this point that the return of the slide |5 will be effected by the cam 16 at a more rapid speed lfor the purpose of saving time and increasing production.v v

When the work slide I5 has returned to its starting position, the completed pinion 51 will be automatically ejected from the ends of the work-supporting spindles 55 and `59 before the insertion of the next gear blank. This is accomplished by the crescent-shaped cam |49 carried by the shaft |95 which swings the knockout lever |35 to cause the tail stock 69 carrying the support spindle 59 to be again moved to the right sufficiently to clear the end of said spindle 59 from the trunnion 56d of the spindle 56. Further movement of the tailstock 60 to the right causes the yoke member |43 attached to the outer end of said tail stock to move the small ro'd |45, and causes the ejector block |59 to drive the pin |54 within the spindle 55 to force the adjacent trunnion 56a. out of the socket therei of. The cut pinion 51 will then drop upon an inclined surface 299 of the slide |5, as best shown in Figs. 1 and 2, locatedbetween the bushed bearings 54 and 6|, and Will roll forwardly and drop olf from the front edge of said slide and be caught in any suitable container 0r basket, not shown, supported on the front edge of the basin-like base in front of the housing I2. f

` After the cut pinion has been discharged in the above manner, the delivery end of the magazine |99 will again move in as already described, and the cycle of operations will be repeated as long as-the machine is in operation.

While there has been disclosedin this specification one form inwhich the invention may be embodied, it is to be understood that this form is shown for the purpose of illustration only, and that the invention is not to be limited to the specific disclosure but may be modified and embodied in various other forms Without dep-artingfrom its spirit. In short, the'invention includes all the modifications and embodiments coming within the scope of the following claims.`

- v Havingthus funyuescribed the invention, whatis claimed as new, and for which it is desired to secure Letters Patent, is:

l l. In a gear bobbingA machine, a rotating hobbi-ng cutter, means for continuously rotating a gear blank while in position to be cut by saidv bing cutter, means for continuously rotating a gear blank while in position to be cut by said cutter, a swinging magazine pivoted on an axis located above said cutter and blank and carrying blanks below said cutter, and'yieldable means for'forcing the lower end of said-magazine toward said cutter to feed an -uncut blank into cutting position. f

v3. In a gear bobbing machine, a rotating hobbing cutter, means for continuously-rotating a gear blank at an angle to the axis of said cutter, a swinging magazine pivoted on an axis located above said cutter and blank and carrying blanks below said cutter, yieldable means for forcing the lower end of said magazine toward said cutter to feed an uncut blank into cutting position,'and cam controlled means for returning said magazine into a clear position after the feeding operation.

4. In a gear hobbing machine, a rotating hobbing cutter, means for continuously rotating a gear blank at an angle to the axis of said cutter, a swinging magazine pivoted on an axis located above said cutter and blank and carrying blanks below said cutter, yieldable means for forcing the lower end of said magazine toward said cutter to feed an uncut blank into cutting position, and positive power-driven means for returning said magazine in to a clear position after the feeding operation.

5. In a gear bobbing machine, a main drive shaft, a bobbing cutter, means connected with said shaft for driving said cutter, a vgear blankcarrying slidable member, cam means connected with said shaft for sliding said member with respect to said cutter during thecutting operation, means connected with said drive shaft for independently rotating said gear blank, a swinging gear blank-carrying magazine, yieldable means connected with said shaft for swinging said magazine to feed a blank to said member, and cam-operated means connected to said shaft for automatically ejecting a completed gear from said member. K 6. In a gear hobbing machine, a main drive shaft, a hobbing cutter, means connected with said shaft for driving said cutter, a gear blankcarrying slidable member, cam means connected to said shaft for sliding said member with respect to said cutter during the cutting operation, meansconnected to said drive shaft for independently rotating said gear blank, a swinging blank-carrying magazine,l cam-controlled means connected with said shaft for operating said swinging magazine to feed a blank to said member, cam-operated means connected to said lshaft for automatically ejecting the .completed gears from said member, and cam-operated clutch mechanism for initiating the operation of said magazine'swinging mechanism and ejecting mechanism at the proper point in the cycle of the machine.

7. In a gear bobbing machine, a rotating hobbing cutter, a gear-blank-carrying member slidable with respectto said cutter and having a headstock and a tailstock, means to feed gear blanks to said member before the cutting operation, means to eject the completed gears aty the conclusion of the cutting operation, said ejecting means including a rotating cam, a lever engaging said. cam, said lever being connected to said tailstockl to move it away from said headstock and withdraw the support from one side of said gear, an ejector rod slidably mounted within said headstock, and means loosely con.- nected with Asaid lever for pushing the other end of said gear out of said headstock to permit said gear to drop out of said member.

8'. In a machine Vfor cutting teeth in a gear blank, a shaft for supporting a gear blank, a

the ends of said gearblank, means to rotate said spindles and said hob in unison, an axially slidable ejector associated with one of said spindles toeject the blank therefrom, means to move one of said spindles relative to the other, and a single cam adapted to actuate said ejector and said spindle moving means.

9. In a machine for cutting teeth in a gear blank having a shaft, a rotatable hob, a slidable carrier, means to slide said carrier, opposit'ely directed spindles mounted on said carrier andadapted to receive the ends of said gear blank shaft, means to rotate said spindles and said hob in unison, an axially slidable. ejector located within one of said spindles to eject the blank shaft therefrom, means to move one of said spindles relative yto the other, means to feed a blank into operating position between said spindles, and a single cam member adapted to control the actuation of said ejector, said spindle moving means, and said blank feeding means and to actuate said carrier sliding means.

l0. In a machine for hob-cutting teeth in a j spur gear pinion, a rotatable hob-carrying spindle, a pair of opposed pinion blank carrying spindles, a holder for said blank spindles adapted to slide axially with respect to said blank, one of said blank spindles being movable away from the other, a pinion blank ejector in the other spindle and adapted to be moved to eject a pinion blank from this spindle, a common drive shaft, change gears drivingly connected to said common drive shaft, an intermediate shaft between said common drive shaft and said hob'spindle, an intermediate shaft between said change gears and said blank spindles, a pair of meshing gears connecting each intermediate shaft with its associated spindles, a pair of meshing gears connecting one of said intermediate shafts with said change gears, another pair of meshing gears connecting the other of said intermediate shafts with said comomn shaft, said shafts andv gears constituting the sole driving means for said spindles, said change gears including an idler-gear adapted to be replaced by other idler gears to vary the speed proportions between said spindles, a cam drivingly connected to said change gears, a lever arm actuated by said cam to slide said spindle holder, and a lever actuated by said cam to move said movable blank spindles and said blank ejector.

1l. In a machine for hob-cutting teeth in a spur gear pinion, a rotatable hob-carrying spindle, a pair of opposed pinion blank carrying spindles, a holder for said blank spindles adapted to slide axially with respect to saidr blank, one

of said blank spindles being movable away from the other, a pinion blank ejector in the other spindle and adapted to be moved to eject a pinion blank from that spindle, a comornn drive shaft, change gears drivingly connected to said common drive shaft, an intermediate shaft between said common drive shaft and said hob spindle, an intermediate shaft between said change gears and said blank spindles, a pair of meshing gears connecting each intermediate shaft with its associated spindles, a pair of meshing gears connecting one of said intermediate shafts with said change gears, another pair of meshing gears connecting the other of said intermediate shafts with said common shaft, said shafts and gears constituting the sole driving means for said spindles, said change gears includingan idler gear adapted to be replaced by other idler gears to vary the speed proportion between said spindles, a cam drivingly connected to said change gears, a lever actuated by said cam to slide said spindle holder, a lever actuated by said cam to move said movable blank spindle and said`blank ejector, a magazine adapted to hold a plurality of pinion blanks and swingable to present one to said spindles below said hob spindle, and means to swing said magazine, said Vmagazineswinging means being controlled by said cam.

12. In a gear hobbing machine, a rotating hobbing cutter, a gear-blank-carrying member slidable with respect to said cutter and having a headstock and a tailstock, means to feed gear blanks to said member before the cutting operation, means to eject the completed gears at the conclusion of the cutting operation, said ejecting means including a cam, a lever engaging said cam, said lever being connected to said tailstock to move `it away from said headstock and withdraw the Support from one side of said gear, an ejector rod slidably mounted within said headstock, and means loosely connected with said lever for pushing the other end of said gear out of engagement with said headstock to permit said gear to drop out of said member.

FREDERICK LUX. 

